Hardened steel round 0.5 mm, Dnipropetrovsk region.

"Steel 40X is an alloyed structural steel described by multiple state standards. It contains elements that are specially introduced so that the steel meets certain specific characteristics. The alloying element here is chromium, as evidenced by the letter "X" in the name of the steel brand. This brand is mainly used in the production of improved parts and parts of increased strength. There are substitutes for steel 40X, presented the following brands: 38X, 40XH, 45X, 401X. The use of 40X steel is very often used for the production of springs and carburetor needles, since these parts are constantly subject to rupture and compression. In addition, the scope of use of 40X steel includes the production of axles, shafts, plungers, bushings, mandrels, rings, bolts, rods, and other parts that require increased strength. Another area of application of this material is the production of forged blanks and fittings. But it should be noted that all these parts must be quenched inмасле with further quenching in it or in the air steel is a rather difficult process, since this brand is difficult to weld. Because of this, welding must be accompanied by constant heating of the products to 200-300 degrees Celsius. Plus, this material is prone to brittleness.
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